The thing is that i understand how we can measure the luminosity of a close star through absolute and apparent magnitude, because we can easily find the distance through trigonometric parallax. What i have understood about standard candles is that if a distant star has a similar luminosity to a close star, its identified as a standard candle. Through that we would know the absolute magnitude of the distant star as it falls in the same category of the close star and thus we can find its distance from earth. However i dont understand how do we find the luminosity of a distant star without the absolute magnitude?